The present invention relates to a signal quality detection scheme, and more particularly, to a signal quality detection circuit for generating a signal quality detection result according to a two-dimensional nominal sampling point pattern and an associated signal quality detection method.
An oscilloscope is a type of electronic test instrument that allows observation of constantly varying signal voltages, and usually displays a two-dimensional plot of one or more signals as a function of time. Hence, the oscilloscope is commonly used to observe the change of an electrical signal (e.g., a voltage signal) over time. The observed waveform can be analyzed for determining signal properties such as amplitude, frequency, distortion and others. However, to use an oscilloscope to measure a signal quality of an electrical signal of a device under test, the associated preparatory work is quite troublesome. Moreover, the oscilloscope is required to use probes to receive signals from the device under test. However, it is possible that the probes of the oscilloscope are unable to have direct contact with the device under test, and are therefore indirectly connected to the device under test via an intermediate medium/structure. As a result, the measured signal quality may be different from the actual signal quality of the electrical signal of the device under test.
The oscilloscope is quite expensive, and may not be affordable for every manufacturer. In addition, the oscilloscope requires calibration, repair, etc. Hence, a considerable maintenance fee of the oscilloscope may be needed. Further, a lot of manpower may be needed to perform the signal quality measurement using the oscilloscope. As a result, using an oscilloscope to measure a signal quality of an electrical signal of a device under test is not a cost-efficient solution.
Thus, there is a need for an innovative signal quality detection scheme capable of detecting actual signal quality of an electrical signal of a device under test (e.g., a dynamic random access memory) without the use of an oscilloscope.